Full-Stack Builder — Product Engineering

Katapult Labs; United States; Remote; USD 112,000 - 156,000; Full time

Benefits offered by this job

Work from Anywhere in LATAM

23 Days PTO per Year

USA Federal Holidays

Monthly Payment in USD

Contractor Agreement with No End Date

Job summary

Katapult Labs is seeking a Full-Stack Builder to join the founding technical team. You will assess and harden the partner’s existing web platform, refactor code for rapid iteration, and deliver end-to-end features with UX-focused functionality.

This role centers on fast delivery, light architectural work, and close collaboration with founders and a product-minded team. There is potential to extend into mobile development as the roadmap evolves.

Qualifications

• Advanced conversational English, since all collaboration happens in English.
• Strong full-stack engineering experience with modern web technologies (frontend and backend).
• Demonstrated ability to work as a builder: shipping fast, with just enough architecture, not over-engineering.
• Comfort working directly with founders and non-technical stakeholders, translating product vision into working software.
• Experience refactoring or hardening an existing early-stage codebase.
• Product analytics tooling (Amplitude, PostHog, or similar).
• Agentic mindset: comfortable using AI coding tools (Cursor, Claude Code, etc.) as part of daily workflow.
• Strong communication skills, comfortable asking clarifying questions and flagging blockers early.

Responsibilities

• Understand and evaluate the current architecture of our partner’s existing web platform.
• Refactor and harden the codebase to support rapid, reliable iteration.
• Build new features end-to-end, working closely with the product lead on UX and engagement-focused functionality.
• Help establish lightweight technical processes (code review, deployment, documentation) as the team scales.
• Collaborate directly with a technical product manager and design lead in a fast-moving, startup environment.
• Be ready to extend work into mobile development as the product roadmap evolves.

Skills

Full-stack engineering

Frontend development

Backend development

Web technologies

Code refactoring

Product analytics tooling

AI coding tools

Communication skills

Advanced English

Tools

Amplitude

PostHog

Job description

About Katapult Labs

Katapult is an AI-first engineering studio connecting senior LATAM talent with startups and companies in the US. We’re not a staff-augmentation shop: every person we put in front of a client represents Katapult, co-creates product, and owns the outcome directly, with no managers or leads acting as a layer in between.

The Role

We’re looking for a Full-Stack Builder to join the founding technical team behind one of our partners, an early-stage product with big ambitions to become a real tech company: web platform, mobile app, and everything in between. Our partner already has a first version of their site live, built by a non-technical founding team full of product ideas. We need someone who can step in, understand and harden the existing architecture, refactor where needed, and help seed the technical process for building product going forward.

This is a builder role, not a heavy-architecture or platform-engineering seat. You’ll move fast, ship with sufficient quality, and work closely with a product-minded team that cares deeply about user experience and engagement. Mobile development isn’t required from day one, but the team expects to build a mobile app down the line, so comfort picking that up matters. If the engagement goes well, this grows into a two-builder team supporting the full platform.

Key Responsibilities

• Understand and evaluate the current architecture of our partner’s existing web platform

• Refactor and harden the codebase to support rapid, reliable iteration

• Build new features end-to-end, working closely with the product lead on UX and engagement-focused functionality

• Help establish lightweight technical processes (code review, deployment, documentation) as the team scales

• Collaborate directly with a technical product manager and design lead in a fast-moving, startup environment

• Be ready to extend work into mobile development as the product roadmap evolves

Requirements

• Advanced conversational English, since all collaboration happens in English

• Strong full-stack engineering experience with modern web technologies (frontend and backend)

• Demonstrated ability to work as a builder: shipping fast, with just enough architecture, not over-engineering

• Comfort working directly with founders and non-technical stakeholders, translating product vision into working software

• Experience refactoring or hardening an existing early-stage codebase

• Product analytics tooling (Amplitude, PostHog, or similar)

• Agentic mindset: comfortable using AI coding tools (Cursor, Claude Code, etc.) as part of daily workflow

• Strong communication skills, comfortable asking clarifying questions and flagging blockers early

Nice to Have

• Prior experience building consumer-facing (B2C) products with high user engagement

• Mobile development experience (native or cross-platform)

• Experience working in a 0-to-1 startup environment alongside a small, fast-moving team

Work-Life Balance

• Work from Anywhere in Latin America: Enjoy the freedom to work remotely from any country in Latin America.

• 23 Days of PTO per Year: Take time to recharge with paid time off, accrued monthly (1.91 days/month).

• USA Federal Holidays

Financial Benefits

• Monthly Payment in USD: Get paid in US dollars, no matter where you are.

• Contractor Agreement with No End Date: Enjoy the stability of a long-term contract.